Retention pond erosion is caused by several factors, the first being how steep the bank is around the pond. Secondly, wind and water motion, and third, animals, waterfowl and crayfish. Muskrats will cause general mayhem by gnawing at the plants underwater, ducks may eat the plants and crayfish will burrow into the bank and eat the roots of the plants. If you see evidence of muskrats or crayfish, you should eradicate that problem before you plant any vegetation around the banks of your pond. Muskrats can be live trapped and relocated.You can relocate the crayfish to a more suitable environment elsewhere. You can build cages or fences around newly planted plants and grasses to keep waterfowl away from your plants until they become established.
Planting vegetation on the edges of your retention pond will help reduce bank erosion. Planting vegetation helps hold the soil in place. Make sure you use several different types of plants to help keep the soil in place. Using vegetation that are native to your area is preferable. Stay away from plants that are prohibited or illegal in your area. There are dozens of plants that will help with bank erosion around your retention pond.
Listed below are some of the plants available that will help to prevent soil erosion and their planting depths.
Manna Grass grows 2-3 feet tall and can be planted up to six inches deep in the water around the banks of your pond.
Carex Grass grows 12-18 inches tall and may be planted to depths of six inches or less.
Zebra Rush grows 2-5 feet tall may be planted up to six inches deep in the water.
Narrow Leaf Cattail (Typha Laxmani) may be planted to depths up to fourteen inches deep.
Variegated Water Celery may be planted from one to six inches deep.
Cardinal Flower (Lobelia Cardinalis) may be planted one to two inches deep or in the bog area of your retention pond.
Thalia Dealbata may be planted up to eight inch depths in the water.
Obedient Plant (Physostegia Leptophylla) may be planted to six inches beneath the surface of the water or in bog soil around the pond.
Arrowhead, such as Sagittaria Latifolia or Sagittaria Japonica may be planted in water depths up to six inches.
Chinese Lizard's Tail may be planted up to seven inches deep.
Golden Club (Orontium Aquaticum) may be planted to depths up to eighteen to twenty four inches deep.
Pontederia Dilatata does well in depths up to twelve inches beneath the surface of the water.
Pontederia Cordata may be planted up to twelve inches beneath the surface of the water.
Variegated Sweetflag (Acorus Calamus Variegata) may be planted up to twelve inches deep.
Arrow Arum may be planted up to five inches deep.
Blue Flag Iris may be planted in up to four inches of water or well above the water level, in moist soil.
Most Louisiana Iris can be planted five to six inches beneath the surface of the water or above the water level in a bog area. (Black Gamecock Iris is the exception and can only be planted up to three inches beneath the surface of the water).